昆虫钠离子通道基因突变及其与杀虫剂抗性关系的研究进展

昆虫电压门控钠离子通道(voltage-gated sodium channel)存在于所有可兴奋细胞的细胞膜上，在动作电位的产生和传导上起重要作用，是有机氯和拟除虫菊酯杀虫剂的靶标位点。在农业和医学害虫控制过程中，由于有机氯和拟除虫菊酯杀虫剂的广泛使用，抗药性问题日益突出。其中，由于钠离子通道基因突变，降低了钠离子通道对有机氯和拟除虫菊酯类杀虫剂的亲和性，从而产生击倒抗性(knock-down resistance, kdr)，已成为抗性产生的重要机制之一。本文综述了昆虫钠离子通道的跨膜拓扑结构、功能、进化及其基因的克隆；更重要的是总结了已报道的40多种昆虫40个钠离子通道基因非同义突变，以及钠离子通道基因选择性mRNA剪接和编辑，以及它们与杀虫剂抗性的关系；也评述了钠离子通道基因突变引起蛋白质结构的改变，从而对杀虫剂抗性的影响机制。这些研究对于进一步鉴定与杀虫剂抗性相关的突变及抗性机制，开发有机氯和拟除虫菊酯类杀虫剂抗性分子监测方法具有重要意义。

Research progress in sodium channel gene mutations and their association with insecticide resistance of insects

The voltage-gated sodium channels of insects exist on the membrane of all excitable cells. Because of their essential role in the generation and transmission of potential action and electrical signaling in excitable cells, sodium channels are the target site of the organochlorine and pyrethroid insecticides. Due to massive use of organochlorines and pyrethroids for the control of agricultural and medical insect pests, the number of insect pests that have developed resistance to these insecticides is drastically increasing. One major mechanism of the resistance is known as knock-down resistance (kdr). Insects exhibiting kdr have reduced target-site (sodium channel) sensitivity to organochlorines and pyrethroids, mainly resulting from one or more nonsynonymous point mutations in the insect sodium channel protein. In this article, we reviewed the transmembrane topology structure, function, evolution and gene cloning of voltage-gated sodium channels. More importantly, we summarized the known 40 nonsynonymous mutations from more than 40 insect species, the mRNA alternative splicing and editing of the sodium channel genes, and their association with insecticide resistance. We also reviewed the insecticide resistance mechanisms due to protein structure changes resulting from these mutations. These researches provide a comprehensive information frame for further identification of mutations and molecular mechanisms associated with organochlorine and pyrethroid resistance, and the development of molecular monitoring methods of the resistance.